Help. With the rotten weather not much else to but raise shooting questions;
1. Am I right that chokes are based on the comparison to the barrel id e.g.; bore of .740, skeet would measure .735, bore .730 skeet would measure .725?
2. chokes could also be done by patterning; distance diameter and percentage?
3. Now the big one, its becoming increasingly popular around our area to see a lot of Cutts installed on the autoloaders. In making some measurements, the inside of the vented part measures 1.070 and the screw-in skeet choke measures .785. Do you know if this was derived by patterning and what’s your opinion of the Cutts?
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Waddayamean “at least the work”! This stuff is priceless. Pure gold. As close to the truth as you are going to get this side of a deodorant ad. It’s free too.
The amount of constriction of the choke is the DIFFERENCE between the bore diameter and the choke. A bore diameter of .725″ and a choke diameter of .720″ would give a constriction of .005″ or what is generally considered to be a “skeet” constriction in 12 gauge. Be aware that there is no universally accepted opinion on how much constriction equals a certain amount of choke.
Choke is actually a measure of PERFORMANCE, not just constriction. Example: A Modified choke in the US is generally considered to be one that throws 60% of its pattern into a 30″ circle at 40 yards (all 12 gauge chokes are patterned into 30″ at 40 yards). Very often .020″ of constriction is required to do this. Thus .020″ constriction is often equated with Modified choke. IC’s 50% is often obtained with .010″ and Full’s 70-75% with .035″.
That said, if you found a shell that patterned really tight and could get a 60% pattern out of it using only .010″ constriction (normally associated with Improved Cylinder), then that .010″ choke would be Modified when shot with that shell. Performance is what counts, not any kind of barrel measurement. Confused yet? Me too.
Obviously, manufacturers have to stamp some kind of choke marking on the barrel. Instead of being honest about it and stamping the numeric constriction on the choke, they take the easy way out and stamp a choke name on it. This is probably a good idea because the average shooters doesn’t really know what the constriction numbers mean, but he does have a vague idea that IC is near, Mod if middlin’ and Full is far. It is also easier for the manufacturer, ganging of tolerances being what they are. Bottom line: If you want to know what you have, you have to pattern with the shell that you are going to use.
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